Elevator control mechanism



p 26, 1939. w. E. SCHEIB N ER 2,174,043

ELEVATOR CONTROL MECHANISM Filed May 16, 1958. 2 Sheets-Sheet l 1 I3 3 l .1 I

WALTER E. SGHEIBNER Gttorneg Patented Sept. 26, 1939 UNITED STATES PATENT OFFICE Application May 16,

1 Claim.

My present invention relates to an improved elevator control mechanism of the type in which brakes are supported on the car and the brakes are controlled by means of the supporting cable 5 for the car. In carrying out my invention a pair of stationary, upright racks are provided in the elevator shaft or elevator well, and complementary pinions are mounted to travel with the elevator or car and roll on the racks under normal conditions. A pair of traction or friction brakes, which co-operate with the rolling pinions, are also mounted to travel with the car, and the brakes are held in disengaged position by the supporting cable of the car while the latter is in proper condition for properly performing its functions.

In connection with the supporting cable and the brakes, safety means are employed, whereby, in the event of parting or breaking of the cable, 20 or in such an emergency where the cable fails to support the car, the brakes are automatically applied, and through the instrumentality of the pinions and racks, the car is brought to stationary position.

Means are also provided for cushioning the sudden stopping or breaking movement of the car, in an emergency, for the purpose of eliminating to a considerable extent the sudden shocks and rebounds accompanying a rapidly descending car under these emergency conditions. The nvention consists in certain novel combinations and arrangements of parts as will hereinafter be more fully set forth and claimed.

In the accompanying drawings I have illustrated one complete example of the physical embodiment of my invention wherein the parts are combined and arranged according to the best mode I have thus far devised for the practical application of the principles of my invention, but it will be understood that various changes and alterations may be made in these exemplifying structures within the scope of my appended claim, without departing from the principles of the invention.

Figure l is a view in elevation showing an elevator or car equipped with the safety devices or control mechanism of my invention.

Figure 2 is a horizontal sectional view, transversely of the elevator well, showing the car in section together with its auxiliary supporting frame; also showing the stationary, upright rackrails in section; and showing the two brake devices in top plan views.

Figure 3 is a detail perspective at one end of 1938, Serial No. 208,179

one of the stationary upright guides or rack-rails for the car.

Figure 4 is a detail sectional view in elevation showing the connection of the supporting cable to the head-beam of the auxiliary frame of the car, and indicating by dotted lines the springaction for automatically operating the brakes in 'an emergency when the cable for any reason fails to support the car.

Figure 5 is an enlarged sectional detail view showing a portion of one of the friction brake devices, transversely of the brake shaft; and Figure 6 is a sectional detail view of one of the brake devices, longitudinally of the shaft, and showing also one of the pinions forming part of the braking mechanism.

In carrying out my invention I utilize two upright, stationary guide rails A and B, one located at each side of the elevator well or elevator shaft, and these rails are securely bolted to the frame of the building, in which the elevator is installed, through the use of the flange or base I. Each guide rail is fashioned with a rack portion 2 extending the full length of the travel of the car, and the guide rail per se as 3 is formed as a free edge of the stationary upright. The guide rails are spaced apart the required distance to permit the vertical travel of the car or elevator 4 between the rails, and the rails at all times maintain the car in its proper erect position.

The car 4 is resiliently mounted in an auxiliary frame for the purpose of eliminating to a substantial degree, the sudden shocks and rebounds that usually accompany an emergency-stop of the elevator or car, and the resilient means here shown comprise a pair of leaf springs 5, 5, mounted beneath the car and supported on a base-beam of the frame that comprises two spaced cross bars 6, 6. The auxiliary frame also includes two upright bars or side bars I and 3, one at each side of the car, and these side bars are joined by an overhead or head-beam fashioned of the two parallel cross bars 9, 9. The base-beam, the side bars, and the head-beam are rigidly bolted together to form a rigid auxiliary frame surrounding the car,

and the car is resiliently supported in this auxil- The leaf springs 5, 5, provide a resilient support between the bottom of the car and the basebeam 6, and a pair of air-checks or pneumatic cushions I2, l2, are mounted on top of the car and connected with the head-beam 9 to absorb and check sudden movements of the car with relation to the head-beam.

In Figure 1 the lower end of the supporting cable !3 is shown and it will be understood that the cable passes upwardly through the elevator well, and over suitable overhead rigging, and thence to the usual power plant for operating the car 4. On the end of the supporting cable I3 is provided a rigid head 14, and a rigidly arranged bolt l5 depends from this head, the bolt passing down through an upright sleeve or housing [6 that is rigidly mounted by attaching plates I! to the cross bars 9, 9 of the head-beam.

The lower end of the sleeve, below the headbeam, is open, but the upper end of the sleeve, above the head-beam, is closed with a head l8 having a central bolt hole to accommodate the bolt or spindle l5. A spring I9, which is coiled about the bolt within the sleeve or housing, is interposed between the head I8 and a springplate 20 which is mounted on the lower end of the bolt, below the head-beam, and a nut lock 21 is provided on the extremity of the bolt to support the plate. The supporting cable 83 is thus provided with a resilient connection to the head-beam of the auxiliary frame, and it will be apparent that the weight of the car compresses the spring so that, under normal conditions the head l8 of the sleeve is spaced below the head I4 of the supporting cable, as indicated by full lines in Figure 4.

Should the support of the cable I3, for any reason, fail or be released, the compressed spring I9 is then free to project downwardly the springplate 20. Two brake-control or safety cables 22 and 23, which are secured to the spring plate 25, and normally held taut by the suspension of the car on the supporting cable, are freed, to permit application of the safety brakes, should the support for the cable l3 fail.

These normally taut safety cables connected at their upper ends to the spring plate 20, pass outwardly and over the top of the car, and are guided by pulleys 24 journaled on the side bars I and 8, down to near the bottom of the car, where they are connected each to a brake lever 25. The two brake levers form parts of two safety brakes that are mounted near the bottom of the auxiliary frame, and each brake lever is mounted on a rock shaft 26 that is journaled to rock in a disk or circular plate 2?. A spring 28 is coiled about each shaft with one end anchored to the brake lever and its other end secured to the plate 2?, and the spring is instrumental in applying the brakes for an emergency application.

A well known type of operating cam 29 is mounted on the rock shaft 26 and this cam coacts with the shoes 30, 36 that are held by a spring 3| in normally inoperative position.

The plate or disk 2?, as seen in Figure 6 is integral with a sleeve 32, and this bearing sleeve is integral with the attaching bracket 33 that is bolted to the side bars 1 and 8, one being bolted to each side bar. The brake shaft 34 of each device is journaled to revolve in one of these bearing sleeves, and each shaft has a pinion 35 keyed at 36 on one end of the shaft for engagement and rolling contact with a rack 2, while at the other end of each shaft a brake drum 3! is keyed, the drum, as usual enclosing the cam 29 and brake shoes 30, 30.

From this description taken in connection with the drawings it will be apparent that the pinions 35 have a rolling contact with the two spaced racks 2, 2, in the up and down movement of the car, and the pinions and drums are free to revolve with their shafts, as long as the pull on the safety cables 22, 23 holds the brake levers 25 in disengaged position of Figure 5 and Figure 6, where the spring 28 holds the cam 29in inoperative position.

In an emergency, when the cable l3 ceases to support the car, the taut safety cables 22, 23, are slacked, permitting the springs 28 to rock the cams 29 to engage the shoes with the drum 31, thus retarding and finally stopping the rotary movement of the drum. The shafts 34 and pinions 35 are also brought to stationary positions with the drum, and the pinions, still in engagement with the complementary racks, support the auxiliary frame and car on the racks of the guide rails.

In thus applying the brakes and automatically stopping the descent of the auxiliary frame and car, the base-springs 5, and the pneumatic cushions I2 at the upper end or top of the auxiliary frame, are instrumental in reducing the shock and rebound incidental to the sudden stopping of the car in its descent. It will be understood that the brake-devices are adjusted to become operative gradually, through a suitable distance for the descent of the auxiliary frame and car, and thereby the suddenness of the emergency stop is materially reduced, and, by the additional cushioning effect of the springs 5 and pneumatic cushions E2, the shock and rebound of the stopped auxiliary frame and car are materially reduced for the safety of passengers and to prevent excessive damage to the elevator.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is:

In a control mechanism for an elevator, the combination with a pair of uprights each having a rack and also forming a guide rail, a rectangular frame supporting and surrounding the elevator, and guides on the frame engaging the guide rails, of a pair of brake devices mounted on the frame and each having a pinion rolling on one of said racks, an operating lever for each brake device and a safety cable connected to each lever, a joint-plate under the frame to which the upper ends of the cables are connected, a suspending cable for the frame passing through and connected with the plate, a sleeve on the frame through which the suspending cable passes, a spring between said plate and the upper end of the sleeve, and spring means for releasing the brakes.

WALTER E. SCI-IEIBNER. 

